Github user hequn8128 commented on a diff in the pull request:
https://github.com/apache/flink/pull/5327#discussion_r170936660
--- Diff:
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/runtime/join/NonWindowLeftJoin.scala
---
@@ -0,0 +1,179 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.flink.table.runtime.join
+
+import org.apache.flink.api.common.state._
+import org.apache.flink.api.common.typeinfo.TypeInformation
+import org.apache.flink.api.java.tuple.{Tuple2 => JTuple2}
+import org.apache.flink.configuration.Configuration
+import org.apache.flink.streaming.api.functions.co.CoProcessFunction
+import org.apache.flink.table.api.StreamQueryConfig
+import org.apache.flink.table.runtime.types.CRow
+import org.apache.flink.types.Row
+import org.apache.flink.util.Collector
+
+/**
+ * Connect data for left stream and right stream. Only use for LeftJoin
without NonEquiPredicates.
+ *
+ * @param leftType the input type of left stream
+ * @param rightType the input type of right stream
+ * @param resultType the output type of join
+ * @param genJoinFuncName the function code of other non-equi condition
+ * @param genJoinFuncCode the function name of other non-equi condition
+ * @param queryConfig the configuration for the query to generate
+ */
+class NonWindowLeftJoin(
+ leftType: TypeInformation[Row],
+ rightType: TypeInformation[Row],
+ resultType: TypeInformation[CRow],
+ genJoinFuncName: String,
+ genJoinFuncCode: String,
+ queryConfig: StreamQueryConfig)
+ extends NonWindowJoin(
+ leftType,
+ rightType,
+ resultType,
+ genJoinFuncName,
+ genJoinFuncCode,
+ queryConfig) {
+
+ // result row, all fields from right will be null
+ private var resultRow: Row = _
+
+ override def open(parameters: Configuration): Unit = {
+ super.open(parameters)
+ resultRow = new Row(resultType.getArity)
+ LOG.debug("Instantiating NonWindowLeftJoin.")
+ }
+
+ /**
+ * Puts or Retract an element from the input stream into state and
search the other state to
+ * output records meet the condition. The result is NULL from the right
side, if there is no
+ * match. Records will be expired in state if state retention time has
been specified.
+ */
+ override def processElement(
+ value: CRow,
+ ctx: CoProcessFunction[CRow, CRow, CRow]#Context,
+ out: Collector[CRow],
+ timerState: ValueState[Long],
+ currentSideState: MapState[Row, JTuple2[Int, Long]],
+ otherSideState: MapState[Row, JTuple2[Int, Long]],
+ isLeft: Boolean): Unit = {
+
+ val inputRow = value.row
+ cRowWrapper.reset()
+ cRowWrapper.setCollector(out)
+ cRowWrapper.setChange(value.change)
+
+ val curProcessTime = ctx.timerService.currentProcessingTime
+ val oldCntAndExpiredTime = currentSideState.get(inputRow)
+ val cntAndExpiredTime = if (null == oldCntAndExpiredTime) {
+ JTuple2.of(0, -1L)
+ } else {
+ oldCntAndExpiredTime
+ }
+
+ cntAndExpiredTime.f1 = getNewExpiredTime(curProcessTime,
cntAndExpiredTime.f1)
+ if (stateCleaningEnabled && timerState.value() == 0) {
+ timerState.update(cntAndExpiredTime.f1)
+ ctx.timerService().registerProcessingTimeTimer(cntAndExpiredTime.f1)
+ }
+
+ // update current side stream state
+ if (!value.change) {
+ cntAndExpiredTime.f0 = cntAndExpiredTime.f0 - 1
+ if (cntAndExpiredTime.f0 <= 0) {
+ currentSideState.remove(inputRow)
+ } else {
+ currentSideState.put(inputRow, cntAndExpiredTime)
+ }
+ } else {
+ cntAndExpiredTime.f0 = cntAndExpiredTime.f0 + 1
+ currentSideState.put(inputRow, cntAndExpiredTime)
+ }
+
+ val otherSideIterator = otherSideState.iterator()
+ cRowWrapper.setEmitCnt(0)
+ // join other side data
+ if (isLeft) {
+ while (otherSideIterator.hasNext) {
+ val otherSideEntry = otherSideIterator.next()
+ val otherSideRow = otherSideEntry.getKey
+ val cntAndExpiredTime = otherSideEntry.getValue
--- End diff --
Make sense.
---
